1. Field of the Invention
The present invention relates to spinel-type ferrimagnetic particles, a process for producing the spinel-type ferrimagnetic particles, and a magnetic recording medium using the spinel-type ferrimagnetic particles. More particularly, the present invention relates to spinel-type ferrimagnetic particles which can exhibit a high coercive force irrespective of fine particles, especially fine particles having an average particle size of 5 to 30 nm, and are excellent in chemical stability and dispersibility; a process for producing the spinel-type ferrimagnetic particles; and a magnetic recording medium using the spinel-type ferrimagnetic particles.
2. Prior Arts
With recent demands for high performance and high-density recording of magnetic recording media such as magnetic tapes, there have been used such magnetic recording media having a high coercive force (Hc), i.e., exhibiting excellent magnetic properties. The magnetic properties of the magnetic recording media have a close relationship with reliability but also an improved weather resistance. Therefore, it has been required to further improve properties of the spinel-type ferrimagnetic particles.